ChatGPT & DALL-E generated panoramic image of a plain with a high-pressure pump, a big pond and a very large pile of gray sand
Why did the oil shoot up? From gravity’s pressure on the rock above it, the compressibility and deformability of the rock, and the incompressibility of the oil. Yes, oil is like water in that when you put pressure on it it doesn’t lose volume. Rock, on the other hand, does lose a bit, and porous rock loses more.
So far this is just a simpler version of fracking and shale oil extraction process, which use high-pressure pumps to force water, chemicals, and sand into underground porous rock formations to create sufficient fissures for oil or gas to flow freely and be extracted. Take away the chemicals and sand, don’t do it where there is a lot of gas or oil, and the water can flow into the empty pores and create a roughly UFO-shaped disk of water underground at the pressure you use to pump it down there.
Want the energy back? Allow the water to flow back through the reversible turbine. The compressible and porous rock decompresses, pushing the water back out. What about the subterranean stuff, geology? That checks out too. There are innumerable pressurized subterranean shale formations that could be exploited. Shale with some mostly impermeable overburden is all that is required. The cap over the sedimentary rocks is very common in oil and gas regions, because that’s what kept the oil and gas underground before we drilled down to the reservoir.
cubic meters per second, which isn’t a lot. But it is under very high pressure, the equivalent again of a dam two kilometers in height. That 3.3 MW of power would turn into about 10 MW of power, in other words. This supports the startup’s claims that they could get 1 to 10 MW of power per well. However, for a 10 MW system, that 320,000 barrels of water is 20 Olympic swimming pools. The reservoir can be deeper than a pool, however, so if it were the size of an American football field, it could be seven meters deep and hold all the water. Soccer fields vary in allowed sizes, so with a big field’s dimensions, it would be 6 meters deep and with a small field, 8 meters deep. Football or soccer fields six to eight meters deep every 500 meters is starting to intrude on the landscape a bit.